diff options
Diffstat (limited to 'src/lib/exchange_api_purse_merge.c')
-rw-r--r-- | src/lib/exchange_api_purse_merge.c | 454 |
1 files changed, 454 insertions, 0 deletions
diff --git a/src/lib/exchange_api_purse_merge.c b/src/lib/exchange_api_purse_merge.c new file mode 100644 index 000000000..c013b29d2 --- /dev/null +++ b/src/lib/exchange_api_purse_merge.c @@ -0,0 +1,454 @@ +/* + This file is part of TALER + Copyright (C) 2022-2023 Taler Systems SA + + TALER is free software; you can redistribute it and/or modify it under the + terms of the GNU General Public License as published by the Free Software + Foundation; either version 3, or (at your option) any later version. + + TALER is distributed in the hope that it will be useful, but WITHOUT ANY + WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR + A PARTICULAR PURPOSE. See the GNU General Public License for more details. + + You should have received a copy of the GNU General Public License along with + TALER; see the file COPYING. If not, see + <http://www.gnu.org/licenses/> + */ +/** + * @file lib/exchange_api_purse_merge.c + * @brief Implementation of the client to merge a purse + * into an account + * @author Christian Grothoff + */ +#include "platform.h" +#include <jansson.h> +#include <microhttpd.h> /* just for HTTP status codes */ +#include <gnunet/gnunet_util_lib.h> +#include <gnunet/gnunet_json_lib.h> +#include <gnunet/gnunet_curl_lib.h> +#include "taler_json_lib.h" +#include "taler_exchange_service.h" +#include "exchange_api_handle.h" +#include "exchange_api_common.h" +#include "taler_signatures.h" +#include "exchange_api_curl_defaults.h" + + +/** + * @brief A purse merge with deposit handle + */ +struct TALER_EXCHANGE_AccountMergeHandle +{ + + /** + * The keys of the exchange this request handle will use + */ + struct TALER_EXCHANGE_Keys *keys; + + /** + * The url for this request. + */ + char *url; + + /** + * Context for #TEH_curl_easy_post(). Keeps the data that must + * persist for Curl to make the upload. + */ + struct TALER_CURL_PostContext ctx; + + /** + * Handle for the request. + */ + struct GNUNET_CURL_Job *job; + + /** + * Function to call with the result. + */ + TALER_EXCHANGE_AccountMergeCallback cb; + + /** + * Closure for @a cb. + */ + void *cb_cls; + + /** + * Base URL of the provider hosting the @e reserve_pub. + */ + char *provider_url; + + /** + * Signature for our operation. + */ + struct TALER_PurseMergeSignatureP merge_sig; + + /** + * Expected value in the purse after fees. + */ + struct TALER_Amount purse_value_after_fees; + + /** + * Public key of the reserve public key. + */ + struct TALER_ReservePublicKeyP reserve_pub; + + /** + * Public key of the purse. + */ + struct TALER_PurseContractPublicKeyP purse_pub; + + /** + * Hash over the purse's contrac terms. + */ + struct TALER_PrivateContractHashP h_contract_terms; + + /** + * When does the purse expire. + */ + struct GNUNET_TIME_Timestamp purse_expiration; + + /** + * Our merge key. + */ + struct TALER_PurseMergePrivateKeyP merge_priv; + + /** + * Reserve signature affirming the merge. + */ + struct TALER_ReserveSignatureP reserve_sig; + +}; + + +/** + * Function called when we're done processing the + * HTTP /purse/$PID/merge request. + * + * @param cls the `struct TALER_EXCHANGE_AccountMergeHandle` + * @param response_code HTTP response code, 0 on error + * @param response parsed JSON result, NULL on error + */ +static void +handle_purse_merge_finished (void *cls, + long response_code, + const void *response) +{ + struct TALER_EXCHANGE_AccountMergeHandle *pch = cls; + const json_t *j = response; + struct TALER_EXCHANGE_AccountMergeResponse dr = { + .hr.reply = j, + .hr.http_status = (unsigned int) response_code, + .reserve_sig = &pch->reserve_sig + }; + + pch->job = NULL; + switch (response_code) + { + case 0: + dr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE; + break; + case MHD_HTTP_OK: + { + struct TALER_Amount total_deposited; + struct GNUNET_JSON_Specification spec[] = { + GNUNET_JSON_spec_fixed_auto ("exchange_sig", + &dr.details.ok.exchange_sig), + GNUNET_JSON_spec_fixed_auto ("exchange_pub", + &dr.details.ok.exchange_pub), + GNUNET_JSON_spec_timestamp ("exchange_timestamp", + &dr.details.ok.etime), + TALER_JSON_spec_amount ("merge_amount", + pch->purse_value_after_fees.currency, + &total_deposited), + GNUNET_JSON_spec_end () + }; + + if (GNUNET_OK != + GNUNET_JSON_parse (j, + spec, + NULL, NULL)) + { + GNUNET_break_op (0); + dr.hr.http_status = 0; + dr.hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED; + break; + } + if (GNUNET_OK != + TALER_EXCHANGE_test_signing_key (pch->keys, + &dr.details.ok.exchange_pub)) + { + GNUNET_break_op (0); + dr.hr.http_status = 0; + dr.hr.ec = TALER_EC_EXCHANGE_PURSE_MERGE_EXCHANGE_SIGNATURE_INVALID; + break; + } + if (GNUNET_OK != + TALER_exchange_online_purse_merged_verify ( + dr.details.ok.etime, + pch->purse_expiration, + &pch->purse_value_after_fees, + &pch->purse_pub, + &pch->h_contract_terms, + &pch->reserve_pub, + pch->provider_url, + &dr.details.ok.exchange_pub, + &dr.details.ok.exchange_sig)) + { + GNUNET_break_op (0); + dr.hr.http_status = 0; + dr.hr.ec = TALER_EC_EXCHANGE_PURSE_MERGE_EXCHANGE_SIGNATURE_INVALID; + break; + } + } + break; + case MHD_HTTP_BAD_REQUEST: + /* This should never happen, either us or the exchange is buggy + (or API version conflict); just pass JSON reply to the application */ + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + break; + case MHD_HTTP_PAYMENT_REQUIRED: + /* purse was not (yet) full */ + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + break; + case MHD_HTTP_FORBIDDEN: + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + /* Nothing really to verify, exchange says one of the signatures is + invalid; as we checked them, this should never happen, we + should pass the JSON reply to the application */ + break; + case MHD_HTTP_NOT_FOUND: + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + /* Nothing really to verify, this should never + happen, we should pass the JSON reply to the application */ + break; + case MHD_HTTP_CONFLICT: + { + struct TALER_PurseMergePublicKeyP merge_pub; + + GNUNET_CRYPTO_eddsa_key_get_public (&pch->merge_priv.eddsa_priv, + &merge_pub.eddsa_pub); + if (GNUNET_OK != + TALER_EXCHANGE_check_purse_merge_conflict_ ( + &pch->merge_sig, + &merge_pub, + &pch->purse_pub, + pch->provider_url, + j)) + { + GNUNET_break_op (0); + dr.hr.http_status = 0; + dr.hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED; + break; + } + break; + } + break; + case MHD_HTTP_GONE: + /* could happen if denomination was revoked */ + /* Note: one might want to check /keys for revocation + signature here, alas tricky in case our /keys + is outdated => left to clients */ + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + break; + case MHD_HTTP_UNAVAILABLE_FOR_LEGAL_REASONS: + { + struct GNUNET_JSON_Specification spec[] = { + GNUNET_JSON_spec_uint64 ( + "requirement_row", + &dr.details.unavailable_for_legal_reasons.requirement_row), + GNUNET_JSON_spec_end () + }; + + if (GNUNET_OK != + GNUNET_JSON_parse (j, + spec, + NULL, NULL)) + { + GNUNET_break_op (0); + dr.hr.http_status = 0; + dr.hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED; + break; + } + } + break; + case MHD_HTTP_INTERNAL_SERVER_ERROR: + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + /* Server had an internal issue; we should retry, but this API + leaves this to the application */ + break; + default: + /* unexpected response code */ + dr.hr.ec = TALER_JSON_get_error_code (j); + dr.hr.hint = TALER_JSON_get_error_hint (j); + GNUNET_log (GNUNET_ERROR_TYPE_ERROR, + "Unexpected response code %u/%d for exchange deposit\n", + (unsigned int) response_code, + dr.hr.ec); + GNUNET_break_op (0); + break; + } + pch->cb (pch->cb_cls, + &dr); + TALER_EXCHANGE_account_merge_cancel (pch); +} + + +struct TALER_EXCHANGE_AccountMergeHandle * +TALER_EXCHANGE_account_merge ( + struct GNUNET_CURL_Context *ctx, + const char *url, + struct TALER_EXCHANGE_Keys *keys, + const char *reserve_exchange_url, + const struct TALER_ReservePrivateKeyP *reserve_priv, + const struct TALER_PurseContractPublicKeyP *purse_pub, + const struct TALER_PurseMergePrivateKeyP *merge_priv, + const struct TALER_PrivateContractHashP *h_contract_terms, + uint8_t min_age, + const struct TALER_Amount *purse_value_after_fees, + struct GNUNET_TIME_Timestamp purse_expiration, + struct GNUNET_TIME_Timestamp merge_timestamp, + TALER_EXCHANGE_AccountMergeCallback cb, + void *cb_cls) +{ + struct TALER_EXCHANGE_AccountMergeHandle *pch; + json_t *merge_obj; + CURL *eh; + char arg_str[sizeof (pch->purse_pub) * 2 + 32]; + char *reserve_url; + + pch = GNUNET_new (struct TALER_EXCHANGE_AccountMergeHandle); + pch->merge_priv = *merge_priv; + pch->cb = cb; + pch->cb_cls = cb_cls; + pch->purse_pub = *purse_pub; + pch->h_contract_terms = *h_contract_terms; + pch->purse_expiration = purse_expiration; + pch->purse_value_after_fees = *purse_value_after_fees; + if (NULL == reserve_exchange_url) + pch->provider_url = GNUNET_strdup (url); + else + pch->provider_url = GNUNET_strdup (reserve_exchange_url); + GNUNET_CRYPTO_eddsa_key_get_public (&reserve_priv->eddsa_priv, + &pch->reserve_pub.eddsa_pub); + + { + char pub_str[sizeof (*purse_pub) * 2]; + char *end; + + end = GNUNET_STRINGS_data_to_string ( + purse_pub, + sizeof (*purse_pub), + pub_str, + sizeof (pub_str)); + *end = '\0'; + GNUNET_snprintf (arg_str, + sizeof (arg_str), + "purses/%s/merge", + pub_str); + } + reserve_url = TALER_reserve_make_payto (pch->provider_url, + &pch->reserve_pub); + if (NULL == reserve_url) + { + GNUNET_break (0); + GNUNET_free (pch->provider_url); + GNUNET_free (pch); + return NULL; + } + pch->url = TALER_url_join (url, + arg_str, + NULL); + if (NULL == pch->url) + { + GNUNET_break (0); + GNUNET_free (reserve_url); + GNUNET_free (pch->provider_url); + GNUNET_free (pch); + return NULL; + } + TALER_wallet_purse_merge_sign (reserve_url, + merge_timestamp, + purse_pub, + merge_priv, + &pch->merge_sig); + { + struct TALER_Amount zero_purse_fee; + + GNUNET_assert (GNUNET_OK == + TALER_amount_set_zero (purse_value_after_fees->currency, + &zero_purse_fee)); + TALER_wallet_account_merge_sign (merge_timestamp, + purse_pub, + purse_expiration, + h_contract_terms, + purse_value_after_fees, + &zero_purse_fee, + min_age, + TALER_WAMF_MODE_MERGE_FULLY_PAID_PURSE, + reserve_priv, + &pch->reserve_sig); + } + merge_obj = GNUNET_JSON_PACK ( + GNUNET_JSON_pack_string ("payto_uri", + reserve_url), + GNUNET_JSON_pack_data_auto ("merge_sig", + &pch->merge_sig), + GNUNET_JSON_pack_data_auto ("reserve_sig", + &pch->reserve_sig), + GNUNET_JSON_pack_timestamp ("merge_timestamp", + merge_timestamp)); + GNUNET_assert (NULL != merge_obj); + GNUNET_free (reserve_url); + eh = TALER_EXCHANGE_curl_easy_get_ (pch->url); + if ( (NULL == eh) || + (GNUNET_OK != + TALER_curl_easy_post (&pch->ctx, + eh, + merge_obj)) ) + { + GNUNET_break (0); + if (NULL != eh) + curl_easy_cleanup (eh); + json_decref (merge_obj); + GNUNET_free (pch->provider_url); + GNUNET_free (pch->url); + GNUNET_free (pch); + return NULL; + } + json_decref (merge_obj); + GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, + "URL for purse merge: `%s'\n", + pch->url); + pch->keys = TALER_EXCHANGE_keys_incref (keys); + pch->job = GNUNET_CURL_job_add2 (ctx, + eh, + pch->ctx.headers, + &handle_purse_merge_finished, + pch); + return pch; +} + + +void +TALER_EXCHANGE_account_merge_cancel ( + struct TALER_EXCHANGE_AccountMergeHandle *pch) +{ + if (NULL != pch->job) + { + GNUNET_CURL_job_cancel (pch->job); + pch->job = NULL; + } + GNUNET_free (pch->url); + GNUNET_free (pch->provider_url); + TALER_curl_easy_post_finished (&pch->ctx); + TALER_EXCHANGE_keys_decref (pch->keys); + GNUNET_free (pch); +} + + +/* end of exchange_api_purse_merge.c */ |